1. Field of the Invention
The present invention relates to a knee protection airbag device which is mounted on a front side of a driver in a vehicle, and can protect a knee of a seated driver using an inflated airbag.
2. Description of the Related Art
In the related art, a knee protection airbag device for a driver includes a folded airbag, an inflator which supplies an inflation gas to the airbag, a case which houses and holds the airbag and the inflator and has a protrusion opening of the airbag, and an airbag cover which covers the protrusion opening of the case and has a door part which is opened by being pressed by the inflating airbag. The knee protection airbag device is mounted below a steering column on a front side of the seated driver (for example, see JP-A-2005-206068 and JP-A-2011-046259). In the case, the protrusion opening is arranged toward a rear side, and the case has a circumferential wall part which surrounds the protrusion opening and extends forward. The airbag cover is made of synthetic resin and covers the protrusion opening. The airbag cover has a door part which can be opened by being pressed by the airbag during inflation, and an outer edge part which surrounds the door part. The airbag cover includes a decorative panel which is arranged to be exposed to the indoor side, and a connection wall part which extends forward from the front side of the decorative panel and is arranged to cover the upper side of the upper wall part on the upper side in the circumferential wall part of the case. The connection wall part of the airbag cover includes an engaging hole which is penetrated vertically. The upper wall part of the case includes a metal engaging hook which protrudes upward to be inserted to the engaging hole. The airbag cover is connected to the case when the engaging hook inserted into the engaging hole is engaged with the connection wall part.
However, in the conventional knee protection airbag device, when a large gap is provided between the upper steering column and the column cover, a metal engaging hook is recognized visually by the driver. Further, although the engaging hook is arranged in a front deep position, if the luster of the metal engaging hook is recognized visually, the driver feels discomfort, and a design property in the vehicle cabin on the front side of the driver is deteriorated. Particularly, by a tilt mechanism which can adjust a vertical position of the steering wheel operated by the driver, the steering column may be excreted to be movable vertically, and may be adjusted such that the large gap is made between the airbag device and the column cover as the upper arranged member thereof. In this case, the engaging hook emitting luster can be easily recognized visually from the large gap.
Incidentally, as the above-described countermeasure, it is considered that a shielding material such as a black felt having flexibility is attached on the column cover side, and the engaging hook which emits the luster is hidden. However, the shielding material is prepared, and the shielding material is necessarily attached in the column cover and the like as the upper arranged member on the upper side of the airbag device, so that the countermeasure cannot be dealt with simply.